21545041 has 8 divisors (see below), whose sum is σ = 24651200. Its totient is φ = 18445968.

The previous prime is 21545039. The next prime is 21545047. The reversal of 21545041 is 14054512.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21545041 - 2¹ = 21545039 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21545047) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9850 + ... + 11836.

It is an arithmetic number, because the mean of its divisors is an integer number (3081400).

Almost surely, 2^21545041 is an apocalyptic number.

It is an amenable number.

21545041 is a deficient number, since it is larger than the sum of its proper divisors (3106159).

21545041 is a wasteful number, since it uses less digits than its factorization.

21545041 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3543.

The product of its (nonzero) digits is 800, while the sum is 22.

The square root of 21545041 is about 4641.6636026321. The cubic root of 21545041 is about 278.2589284027.

Adding to 21545041 its reverse (14054512), we get a palindrome (35599553).

The spelling of 21545041 in words is "twenty-one million, five hundred forty-five thousand, forty-one".